10/01/2026
🐴ℹ️ Information for Horse Owners ℹ️🐴
🌞 Anhidrosis – No Sweat 🐴
The Australian summer is well and truly here, and sweating is one of the most important ways horses regulate their body temperature. When this system fails, the consequences can be serious.
Anhidrosis, also known as non-sweaters, dry coat syndrome, or blowers and puffers, describes a reduced or complete inability to sweat.
What is anhidrosis?
Anhidrosis occurs when a horse partially or completely loses its ability to sweat. Without effective sweating, horses struggle to cool themselves and are at risk of overheating, particularly in hot, humid climates common across much of Australia.
Signs of anhidrosis
Common signs may include:
• Minimal or absent sweating after exercise
• Rapid breathing or flared nostrils after light work
• Lethargy, reduced performance, or reluctance to exercise
• Dry, flaky coat or patchy hair loss
• Elevated body temperature after work
• In severe cases, collapse or even death
How is anhidrosis diagnosed?
Diagnosis is often based on clinical signs and history. Intradermal sweat testing may be used to confirm the condition. This involves injecting small amounts of sweat-stimulating drugs (such as terbutaline, salbutamol or epinephrine) into the skin and observing the sweating response. Horses with anhidrosis show little or no reaction compared with normal horses.
Managing anhidrosis
There is no single cure, but careful management can help affected horses stay comfortable:
• Environmental management – shade, fans, misters and constant access to cool water
• Clipping – helps reduce heat retention
• Exercise modification – work during the coolest parts of the day and reduce intensity
• Nutrition and electrolytes – use electrolytes and consider anhidrosis-specific supplements under veterinary guidance. Some evidence suggests vitamin E may be beneficial, and some owners report benefit with vitamin B supplementation
• Active cooling – cold hosing, ice packs and cooling sprays
• Alternative therapies – some owners report benefit with acupuncture or herbal supplements, though scientific evidence is limited
When to call the vet
Heat stress and heat stroke are emergencies. Contact your veterinarian urgently if your horse shows persistent body temperature above 39.5 °C, muscle tremors, weakness, collapse, or severe respiratory distress.
With veterinary guidance and attentive management, many horses with anhidrosis can continue to live comfortable, active lives. If you’re concerned your horse may not be sweating normally, speak with your equine veterinarian early.
